Seattle is turning to a familiar name to provide backfield depth in the wake of Marshawn Lynch's retirement.
The front office neglected to tender Michael as a restricted free agent earlier this month, which suggests he is returning at a salary below the $1.67 million he would have collected.
Long viewed as a tantalizing power/speed prospect with maturity concerns, Michael finally saw the light after bouncing around the league.
"I think he's more humble than he was," coach Pete Carroll said in January.
"He's just done a marvelous job in a very short time. We have nothing but the highest of expectations. This is a classic example of if you just keep hoping and you stay with it and you give guys chances that sometimes they come right through for you."
Michael ended up averaging 4.4 yards on 60 late-season carries, ingratiating himself to Seattle's coaching staff.
Michael offers premium insurance in case Rawls suffers a setback in his return from a mid-December ankle fracture.